Security fence spike

ABSTRACT

The security fence spike is attached to the upper rail of a chain link security fence or the like, to project generally diametrically through a coil of razor wire or concertina wire strung along the upper rail of the fence. The security spike is a rigid metal projection, and resists collapse when a heavy sheet of material or blanket is tossed over the coiled wire atop the fence by a person(s) attempting to scale the fence. A row of spikes is preferably installed along the upper rail of the fence, threatening injury to anyone attempting to scale the fence even after covering a coil of razor wire or the like atop the fence. The security spike is formed of sheet metal bent to form a triangular cross section for rigidity and strength. The spike is attached to a brace band, which, in turn, is clamped to the fence.

BACKGROUND OF THE INVENTION

1. Field of the Invention

The present invention relates generally to fences and similar barriers. More particularly, the present invention comprises a spike for installation along the upper rail or edge of a security fence having coiled razor wire or concertina wire extending therealong.

2. Description of the Related Art

Fences have been used for delineating property lines and borders and for security purposes for a considerable period of time. Fence materials have evolved from the use of natural or roughly processed materials (e.g., stone and split rail) to manufactured or highly processed materials, e.g. milled wood slats for decorative fencing, or heavy wire chain link security fencing, etc.

In the case of security fencing, there is generally a consideration of the balance between cost and overall security. For example, a conventional chain link fence provides a moderate deterrent effect at reasonable cost, but persons who are determined to cross the fence can do so by climbing such a fence. A person in reasonably good physical condition does not find such a task to be excessively difficult.

Accordingly, further deterrent elements have been developed for security fences. An example of such a deterrent element is the installation of barbed wire strands along the upper rail or edge of the fence. Coiled razor wire or concertina wire is also sometimes installed along the upper rail or edge of fencing to enhance security. Such barbed or razor wire installations significantly increase the difficulty in scaling such a fence, as it is most difficult to cut the security wire along the upper edge of the fence while scaling the fence without additional equipment (ladders, etc.).

Nevertheless, as security fencing has become more difficult to breach, persons wishing to scale or breach such a fence have developed further means and techniques for doing so. In the case of fencing with coiled razor wire or concertina wire installed along its upper rail, persons have been known to toss a heavy blanket or heavy fabric sheet (e.g., canvas, etc.) over the coiled wire to protect themselves from the barbs or razor elements of the wire while scaling the top of the fence. The use of such a blanket or the like obviates the deterrent effect of the coiled wire, and in fact, the coiled wire installed along the upper edge of the fence may facilitate scaling the fence when a blanket or the like is tossed over the coiled wire.

Thus, a security fence spike solving the aforementioned problems is desired.

SUMMARY OF THE INVENTION

The security fence spike is a sharpened spike stamped or otherwise formed of sheet metal to form a triangular cross section for rigidity and strength. The spike is installed along the upper rail of a security fence, preferably within the diameter of a coil of razor wire or concertina wire strung along the upper rail of the fence. The spike may be installed using a brace band for chain link fencing by attaching the spike to the band and then clamping the band to the upper rail of the fence. The spike serves as a rigid element, which maintains its rigid extension even though the otherwise surrounding razor or concertina wire is crushed by covering with a blanket or heavy sheet of material or the like, thus deterring persons from scaling the fence.

These and other features of the present invention will become readily apparent upon further review of the following specification and drawings.

BRIEF DESCRIPTION OF THE DRAWINGS

FIG. 1 is an environmental, front elevation view of the upper portion of a length of chain link fence incorporating a plurality of security fence spikes according to the present invention.

FIG. 2 is an exploded perspective view of a security fence spike according to the present invention, showing alternative attachments to a brace band.

FIG. 3 is a section view through lines 3-3 of FIG. 2.

Similar reference characters denote corresponding features consistently throughout the attached drawings.

DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS

The present invention relates to a security fence spike for attachment to a security fence, particularly for attachment to a fence having a coil of razor or concertina wire disposed along the upper edge or rail thereof to discourage climbing the fence. The security fence spike, when installed along the upper rail of the fence and within the coil of wire, precludes crushing the coil of wire with a blanket or heavy sheet of material to protect persons attempting to scale the fence. The invention may also extend to a security fence incorporating a row of such spikes installed thereon.

FIG. 1 of the drawings shows a chain link security fence 10 incorporating a row of the security fence spikes 22 of the present invention. The security fence 10 includes substantially vertical posts or uprights 12, with the upper ends 14 of the posts 12 being connected by an upper rail 16, or series of rail segments. A chain link mesh 18 extends across the upright posts 12. The chain link material 18 may be attached to the posts 12 and to the upper rail 16 by a series of chain link fence brace bands, with an exemplary band being shown in FIG. 2 of the drawings and discussed further below. The security fence 10 of FIG. 1 includes a coil of razor wire or concertina wire 20 extending along and above the upper rail 16 generally parallel thereto in order to enhance the security provided by the fence 10 by making the fence 10 more difficult to scale.

The function of the razor wire or concertina wire coil 20 is to inflict injury to anyone who reaches the top of the fence 10 and who attempts to work through or over the wire coil 20, thereby dissuading persons from making the attempt. In response, individuals attempting to cross such a fence 10 have been known to toss a relatively thick and/or heavy blanket or other sheet of material over the top of the fence 10 and coiled wire 20, with the blanket providing protection for the person crossing the wire coil 20 as he or she scales the fence 10. The weight of the heavy blanket or sheet, particularly as the person crosses over the wire coil 20, tends to crush the wire coil 20, thereby facilitating crossing over the top of the fence 10.

In order to prevent such a crossing, the security fence spike 22 is installed along the upper rail 16, or, preferably, a plurality of closely spaced spikes 22 is attached to the upper rail 16 and extends generally upwardly therefrom, as shown in FIG. 1. FIG. 2 provides a detailed, exploded perspective view of a single exemplary spike 22, as well as the apparatus used for attaching the spikes 22 to the upper rail 16 of the fence 10. Each spike 22 comprises a thin, elongate projection of sheet material (preferably galvanized steel, although other suitable materials may be used) having a blunt fence attachment end with a flat mounting tab 24 having an attachment hole 26 therethrough.

The mounting tab 24 extends from a spike body portion 28, with the body portion 28 being stamped or otherwise folded from a single sheet of material to form a rigid, closed, triangular cross-sectional shape having sides 28 a, 28 b, and 28 c defining a hollow center or interior 30, as shown in the cross-sectional view of FIG. 3. The metal or material blank from which the spike 22 is formed is tapered to a sharp distal tip 32 opposite the blunt fence attachment end tab 24, with the end tab 24 being an extension of one of the three sides 28 a/28 b/28 c, e.g., the central side 28 b. Alternatively, the flat blank pattern could be formed asymmetrically, with the flat end tab 24 extending from one of the outboard sides of the blank, i.e., side 28 a or 28 c.

Each spike 22 is secured to the upper rail 16 of the fence 10 by a generally circular brace band 34, as shown in FIG. 2. The brace bands 34 are generally conventional, and are commonly used to attach the chain link mesh or screen material 18 to the fence post and rail structure 12 and 16. However, the brace bands 34 are modified by forming a spike attachment hole 36 therethrough, generally diametrically opposite their two opposed clamp lugs or ears 38. The mounting tab 24 of the spike 22 is secured to the brace band 34 by a spike fastener (e.g., self-tapping sheet metal screw 40 a, or, alternatively, a rivet 40 b, etc.), which passes through both of the holes 26 and 36 respectively of the attachment end 24 of the spike 22 and of the brace band 34. Preferably, the spike 22 is installed tangentially to the brace band 34, as shown in FIGS. 1 and 2, so that the spike 22 is disposed normal to the axis of the upper rail 16. Alternatively, the spike 22 may be attached to the brace band 34 by means of a spot weld or other suitable attachment.

The brace band 34 is preferably secured to the upper rail 16 of the fence 10 by a tamper-proof brace band fastener assembly, e.g., the tamper-proof machine screw 42 a and lock nut 42 b shown in FIG. 2, permanently securing the brace band 34 to the security fence 10. Such security screws or tamper-proof screws 42 a are provided with driving slots having slopes to one side, precluding a screwdriver blade from gaining purchase against the side of the slot to unscrew the fastener. By providing a lock nut 42 b, rotation of the lock nut by a suitable tool only results in the screw rotating as well, with the assembly remaining secured.

The cylindrical configurations of the upper rail 16 and brace band 34 allow the brace band (and its attached spike 22) to be rotated about the circumference of the upper rail 16 to adjust the angle of the spike 22 relative to the plane of the fence, with the elongate axis of the spike 22 remaining normal to the axis of the upper rail 16. Alternatively, the base of the spike body 28 may be bent at its juncture with the mounting tab 24 to adjust the angle of the spike 22 if the fastener assembly 42 a, 42 b has been tightened to preclude rotation of the brace band 34 about the circumference of the upper rail 16.

The length of the spike body portion 28 of the spike 22 is preferably no greater than the diameter of the wire coil 20. This places the distal tip portion 32 of the spike 22 within the interior of the wire coil 20, as shown in FIG. 1. This precludes an individual from grasping the distal portion of the spike 22 outside of the wire coil 20 and bending the spike 22 downward to allow a blanket to be tossed over the wire coil 20 without the spikes 22 penetrating the blanket as the wire coil is compressed.

In order to accomplish this with the spike tips 32 contained within the wire coil 20, an individual would have to reach into the razor or concertina wire coil 20 to access the spike body 28, thus likely resulting in injury to the individual unless extensive protective apparel were being worn. However, longer spikes 22 may be provided to extend beyond the diameter of the wire coil 20, if desired. Accordingly, the present security fence spikes 22 and their various attachment means provide a cost effective deterrent, which significantly increases the effectiveness of a razor or concertina wire coil installed atop a security fence.

It is to be understood that the present invention is not limited to the embodiments described above, but encompasses any and all embodiments within the scope of the following claims. 

1. A spike for a security fence, comprising a thin, elongate projection of sheet material having a blunt fence attachment end, a sharply pointed distal tip opposite the fence attachment end, and a spike body extending from the fence attachment end to the distal tip, the spike body being folded into a rigid, closed, triangular cross section having a hollow center.
 2. The spike for a security fence according to claim 1, wherein the fence attachment end of the projection further comprises a flat tab extending from the spike body.
 3. The spike for a security fence according to claim 1, further including a brace band, the fence attachment end of the projection being attached substantially tangentially to the brace band.
 4. The spike for a security fence according to claim 3, further including a tamper-proof fastener securing the brace band to the security fence.
 5. The spike for a security fence according to claim 1, wherein the projection is formed of sheet metal.
 6. A spike for a security fence, comprising: a thin, elongate projection of sheet material having a blunt mounting tab, the tab having an attachment hole formed therethrough, the projection having a sharply pointed distal tip opposite the mounting tab, and a spike body extending from the mounting tab to the distal tip; a brace band having an attachment hole formed therethrough; and a spike fastener extending through the mounting tab attachment hole and through the brace band attachment hole, the fastener securing the mounting tab to the brace band.
 7. The spike for a security fence according to claim 6, wherein the spike body is folded into a rigid, closed, triangular cross section having a hollow center.
 8. The spike for a security fence according to claim 6, wherein the projection is formed of sheet metal.
 9. The spike for a security fence according to claim 6, wherein the spike fastener is selected from the group consisting of screws and rivets.
 10. The spike for a security fence according to claim 6, further including a tamper-proof brace band fastener securing the brace band to the security fence.
 11. A security fence, comprising: a plurality of substantially vertical posts, each of the posts having an upper end; an upper rail having a substantially cylindrical cross section, the rail extending between the upper end of the posts; and a plurality of spikes extending upward from the upper rail opposite the posts, each of the spikes being a thin, elongate projection of sheet material having a blunt fence attachment end, a sharply pointed distal tip opposite the fence attachment end, and a spike body extending from the fence attachment end to the distal tip.
 12. The security fence according to claim 11, further including a chain link mesh disposed across the vertical posts, the mesh being attached to the vertical posts and to the upper rail.
 13. The security fence according to claim 11, further including a coil of razor wire secured to, and extending immediately above and parallel to, the upper rail, the coil substantially surrounding and enclosing each of the spikes therein.
 14. The security fence according to claim 11, wherein each of the spikes has a spike body extending from the fence attachment end to the distal tip, the spike body being folded into a rigid, closed, triangular cross section having a hollow center.
 15. The security fence according to claim 14, wherein each of the spikes is formed of sheet metal.
 16. The security fence according to claim 14, wherein the fence attachment end of each of the spikes further comprises a flat mounting tab extending from the spike body.
 17. The security fence according to claim 14, further including: a plurality of chain link fence brace bands, each of the brace bands having an attachment hole formed therethrough, the brace bands being secured about the upper rail; and a spike fastener extending through the fence attachment end of each of the spikes and corresponding one of the chain link fence brace bands in order to secure the spikes to a corresponding one of the chain link fence brace bands substantially tangential thereto.
 18. The security fence according to claim 17, wherein the spike fastener is selected from the group consisting of screws and rivets.
 19. The security fence according to claim 17, further including a tamper-proof brace band fastener securing the brace band to the security fence. 